U.S. Pat. No. 7,922,016 B1 discloses rotary bearing for ratably supporting an article-carrying member at a supporting column of a rotary fitting of a shelf system. The rotary bearing is built by a pin which transversally extends through a transverse clearance hole in the supporting column. The pin comprises a head whose diameter is enlarged as compared to that is of its shank. Further, the pin comprises arcuate clamping arms which in circumferential direction extend from the head around the supporting column to secure the pin in place on the supporting column. The article-carrying member is provided with a counter bearing which has two circular tracks at its underside. The circular tracks are arranged on different levels in axial direction along the supporting column and extend around the supporting column. The circular track at the higher level is supported by the head of the pin, whereas the circular track at the lower level is supported by the free end of the pin projecting through the supporting column. Both circular tracks have recesses which are offset from one another by 180°. The head of the pin and its free end enter the two recesses simultaneously and in this way define a basic position in rotation for the article-carrying member.
U.S. Patent Application Publication 2011/0127228 A1 discloses a rotary fitting having a rotary bearing for rotably supporting an article-carrying member at a supporting column of the rotary fitting. The rotary bearing comprises a supporting ring having a circular track at its top face which is in engagement with a counter bearing of the associated article-carrying member. The supporting ring is mounted to the supporting column by means of a pin. The pin extends through a transverse clearance hole in the supporting column. The ends of the pin projecting beyond the supporting column are received by the underside of the supporting ring such that the supporting ring is fixed in position and in rotation on the supporting column.